Musgraves is up for four Grammy Awards, including the all-genre best new artist category, at Sunday's show, and on Thursday she and her band rehearsed "Follow Your Arrow," a song that didn't crack country music's Top 20 but helped galvanize national attention for the 25-year-old singer-songwriter. Written with Brandy Clark and Shane McAnally, the song is both playful and poignant, advising listeners to "say what you think" and "love who you love," over a soundscape that leans to country tradition.

A year ago, Musgraves was well-loved in the Nashville music community but little known outside of Music City. This weekend, she'll be seen and heard by what will likely be an audience of more than 25 million. On Thursday, she smiled, swayed and sang like a veteran, drawing applause from the 100-or-so show professionals still in the building for what was the final run-through of the day.